Thesis (M.S.) in Physics--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 45-46).

No description available.

The Kafue Flats floodplain wetland system in southern Zambia is under increasing climate and human pressures. Firstly, drought episodes appear more prevalent in recent years in the region and secondly, two dams were built on the lower and upper ends of the wetland in 1972 and 1978, respectively, across the Kafue River which flows through the wetland. The study uses multi-temporal remote sensing to assess change in extent and vigour of green vegetation, and extent of water bodies and dry land cover on the Kafue Flats. The change detection's management value is assessed. Four normalised, co-registered digital Landsat images from 24 September 1984, 3 September 1988, 12 September 1991 and 20 September 1994 were used. The main change detection method used was comparison of classifications, supplemented by Normalised Difference Vegetation Index (NDVI) and Principal Component Analysis (PCA) change detection. Ancillary land use and environmental data were used in interpreting the change in the context of cause and effect. The results indicate inconsistent trends in the changes of most land cover classes, as a result of manipulation of the wetland by man through annual variations in the timing and magnitude of regulated flows into the wetland, as well as burning. However, the results also show spatial reduction in the wetland's dry season dense green reed-grass vegetation in upstream sections which are not affected by the water backing-up above of the lower dam. Sparse green vegetation is replacing the dense green vegetation in these upstream areas. It is inferred that this dry season degradation of the wetland threatens bird species which may use the reeds for dry season nesting. It is proposed that ground surveying and monitoring work at the micro-habitat level is necessary to ascertain the implications of the losses. It is concluded that, in spite of difficulties, multi-temporal remote sensing has a potential role in wetland change assessment on the Kafue Flats at the community level, but that it needs to be supplemented by targeted, micro-habitat level ground surveys.

No description available.

Classical fabrication methods alone do not enable manufacturing of large flat mirrors that are much larger than 1 meter. This dissertation presents the development of enabling technologies for manufacturing large high performance flat mirrors and lays the foundation for manufacturing very large flat mirrors. The enabling fabrication and testing methods were developed during the manufacture of a 1.6 meter flat. The key advantage over classical methods is that our method is scalable to larger flat mirrors up to 8 m in diameter.Large tools were used during surface grinding and coarse polishing of the 1.6 m flat. During this stage, electronic levels provided efficient measurements on global surface changes in the mirror. The electronic levels measure surface inclination or slope very accurately. They measured slope changes across the mirror surface. From the slope information, we can obtain surface information. Over 2 m, the electronic levels can measure to 50 nm rms of low order aberrations that include power and astigmatism. The use of electronic levels for flatness measurements is analyzed in detail.Surface figuring was performed with smaller tools (size ranging from 15 cm to 40 cm in diameter). A radial stroker was developed and used to drive the smaller tools; the radial stroker provided variable tool stroke and rotation (up to 8 revolutions per minute). Polishing software, initially developed for stressed laps, enabled computer controlled polishing and was used to generate simulated removal profiles by optimizing tool stroke and dwell to reduce the high zones on the mirror surface. The resulting simulations from the polishing software were then applied to the real mirror. The scanning pentaprism and the 1 meter vibration insensitive Fizeau interferometer provided accurate and efficient surface testing to guide the remaining fabrication. The scanning pentaprism, another slope test, measured power to 9 nm rms over 2 meters. The Fizeau interferometer measured 1 meter subapertures and measured the 1.6 meter flat to 3 nm rms; the 1 meter reference flat was also calibrated to 3 nm rms. Both test systems are analyzed in detail. During surface figuring, the fabrication and testing were operated in a closed loop. The closed loop operation resulted in a rapid convergence of the mirror surface (11 nm rms power, and 6 nm rms surface irregularity). At present, the surface figure for the finished 1.6 m flat is state of the art for 2 meter class flat mirrors.

Thesis (Ph. D.)--Massachusetts Institute of Technology, 1993. / "Doctoral dissertation." "February 1993." At head of title: Woods Hole Oceanographic Institution, Massachusetts Institute of Technology. Includes bibliographical references (p. 205-214).

No description available.

PINHEIRO, Flávia Costa. Política de preços como uma estratégia competitiva para o mercado de flats em Fortaleza. 2006. 68f. Dissertação (mestrado profissional) - Programa de Pós-Graduação em Economia CAEN, Universidade Federal do Ceará Fortaleza-CE, 2006. / Submitted by Mônica Correia Aquino (monicacorreiaaquino@gmail.com) on 2013-08-06T19:49:05Z No. of bitstreams: 1 2006_dissert_fcpinheiro.pdf: 465256 bytes, checksum: 8caa48fcffacd145a26326bd3774d226 (MD5) / Approved for entry into archive by Mônica Correia Aquino(monicacorreiaaquino@gmail.com) on 2013-08-06T19:49:15Z (GMT) No. of bitstreams: 1 2006_dissert_fcpinheiro.pdf: 465256 bytes, checksum: 8caa48fcffacd145a26326bd3774d226 (MD5) / Made available in DSpace on 2013-08-06T19:49:15Z (GMT). No. of bitstreams: 1 2006_dissert_fcpinheiro.pdf: 465256 bytes, checksum: 8caa48fcffacd145a26326bd3774d226 (MD5) Previous issue date: 2006 / The objective this project is to establist operational limits of a policy of differentiated princing for different seasons of demanda in hotel enterprises. This policy has iniated from the growth n demand in the Fortaleza market. An economically coherent model is estimated to establish the demand for price that affers a just financial return in the market.The main conclusion of this study is that demand, altough non-eslastic, adjusts to the practice of price differentiation that promote the growth of the “ Receita de Hospedagem” of the avaiable rooms (revpar) in the sector of flats. The calculations used to determine the ideal “revpar” allow for profitability to the manager of a hotel enterprise in that they define the practices that determine the gaia possibilities of the investitor. / O presente trabalho analisa a política de fixação de preços diferenciados de um empreendimento imobiliário que exerce a atividade hoteleira. Após estudar a evolução da demanda no mercado de Fortaleza e o comportamento dos preços praticados nos anos de 2003 a 2005 de uma amostra selecionada como exemplo, desenvolve-se um modelo econométrico de demanda. A partir dos resultados estatísticos, constrói-se uma análise de fixação de tarifas e a respectiva compatibilidade entre demanda, preço e rentabilidade financeira. Este estudo mostra que é possível adequar as práticas de diferenciações de tarifas que promovem o aumento da Receita de Hospedagem com ganhos de vantagem competitiva perante os concorrentes do segmento de flats. O cálculo adotado para a determinação da receita auferida, fornece subsídios ao gerente do empreendimento hoteleiro no sentido de definição de práticas que facilitam as possibilidades de rendimento do investidor.

nÃo hà / The objective this project is to establist operational limits of a policy of differentiated princing for different seasons of demanda in hotel enterprises. This policy has iniated from the growth n demand in the Fortaleza market. An economically coherent model is estimated to establish the demand for price that affers a just financial return in the market.The main conclusion of this study is that demand, altough non-eslastic, adjusts to the practice of price differentiation that promote the growth of the â Receita de Hospedagemâ of the avaiable rooms (revpar) in the sector of flats. The calculations used to determine the ideal ârevparâ allow for profitability to the manager of a hotel enterprise in that they define the practices that determine the gaia possibilities of the investitor. / O presente trabalho analisa a polÃtica de fixaÃÃo de preÃos diferenciados de um empreendimento imobiliÃrio que exerce a atividade hoteleira. ApÃs estudar a evoluÃÃo da demanda no mercado de Fortaleza e o comportamento dos preÃos praticados nos anos de 2003 a 2005 de uma amostra selecionada como exemplo, desenvolve-se um modelo economÃtrico de demanda. A partir dos resultados estatÃsticos, constrÃi-se uma anÃlise de fixaÃÃo de tarifas e a respectiva compatibilidade entre demanda, preÃo e rentabilidade financeira. Este estudo mostra que à possÃvel adequar as prÃticas de diferenciaÃÃes de tarifas que promovem o aumento da Receita de Hospedagem com ganhos de vantagem competitiva perante os concorrentes do segmento de flats. O cÃlculo adotado para a determinaÃÃo da receita auferida, fornece subsÃdios ao gerente do empreendimento hoteleiro no sentido de definiÃÃo de prÃticas que facilitam as possibilidades de rendimento do investidor.

Amphibians worldwide are declining, increasing the demand for monitoring populations of many threatened amphibians, including the South African Critically Endangered micro frog (Microbatrachella capensis). I attempted to improve ongoing monitoring efforts by determining the calling ecology of the micro frog population on the Cape Flats. I used acoustic spatial capture recapture to calculate call density and identify the main factors that determine periods of maximum frog calls. Increased calling behaviour was found early in the season and in response to rainfall. In addition, micro frogs were found to call more at night than during the day. This suggests that future monitoring of this species should occur at night, after rain, and early in the winter breeding season. From the call density estimates, I calculated the size of the micro frog population on the Cape Flats to be about 200 adult frogs when an equal sex ratio of adult males and females is assumed. Future monitoring and conservation efforts should take into consideration this baseline population estimate and keep track of any demographic trends in the population.